Cira Green
Philadelphia, PA

Awards

2015 DVGBC Groundbreaker Award

2013 AIA PA Honor Award

Assemblies

6.00 - 30.00 inches of media

Cira Green is an iconic, publicly-accessible skyline amenity space atop a nine story parking garage in Philadelphia. As the landscape architect, Roofmeadow designed the roofscape to manage stormwater in all vegetated and hardscape plaza areas. Thin under-pavement pancake cisterns beneath the plaza and walkways slowly release captured rainwater into adjacent planting beds. Sloping lawns, perennial beds, ornamental meadow drifts, and shade trees soak up both direct rainfall and water detained in the ‘blue roof’ cisterns below the paving. The interwoven blue-green roof strategies provide a unique approach to holistic stormwater management. This hybrid design provides enhanced runoff volume reduction, additional runoff rate reduction, and water quality treatment in comparison to either on-roof planting or detention alone. A fundamental distinction of this design concept is that evapotranspiration substitutes for infiltration, providing an equivalent process for runoff reduction in a rooftop context as is generally valued on ground-level landscapes.